Whatever Happened to That Storyline?

I thought that I had a pretty good grasp on every episode of Seinfeld. I've either heard about them or watched them. Plus, since it's always been on one TV channel late at night for basically my entire life I've watched several of them more than once. I haven't paid as much attention to the pilot though because it always seemed underdeveloped and awkward. I recently watched the pilot again and I was really curious why this one plotline was dropped. I don't remember this ever being mentioned again but in the pilot Kramer hasn’t been out of the building in 10 years. I think this would explain a lot about his character, but I don't remember another episode where it's mentioned again. So I have a few questions for those Seinfeld fans who may read this: 1. Is this mentioned again? 2. Would you have laughed at it if this storyline would've continued?